This one is for those of you who treated yourselves to the hilarious and highly entertaining R-rated treat that is "21 Jump Street." If you haven't yet seen the box office champ, hurry up and get to a theater already! Also, don't read any more of this post because we're going into SPOILER territory about one of the last (and most outrageous) scenes in the film.

Consider yourselves alerted as we turn to the film's very funny scene stealers Dave Franco and Rob Riggle, for their sordid tale about how Riggle ended up with an unsavory prop in his mouth.

"This one they allowed us to really go off book," Franco told MTV News recently about the amount of improv that was encouraged during filming. "In working with guys like Rob and Jonah [Hill] who are at the top of their game in terms of improvising, there is a lot of really funny stuff in the script but a lot of times we'd throw everything to the side for a take or two. Rob had us in tears. There's one part where Rob picks up his own severed penis with his mouth."

"That sentence is one of the best sentences I've ever heard," Riggle chimed in with a chuckle, which sent Franco into giggles himself.

"[We all thought] 'Of course this will never be in the movie,' but they kept it in, which I've heard during test screenings is half the audience's favorite scene and half of their least favorite scene."

"It wasn't scripted," Riggle revealed. "We got there that night and generally when you start improvising things start to heighten and so that's what happened."

"It wasn't on the page so they didn't prepare for it, so they literally went and got a banana from craft services and then they cut it in half and put blood on it and put it in the street," Riggle added. "And I go, 'Why did you cut it in half? You're killing me.'"

We then pointed out the fact that the audience has no idea where they might have severed the penis, so Riggle shouldn't get hung up on any size jokes.

"Good point," he said. "I should have just said it was the tip."

Tell us what you thought of "21 Jump Street" in the comments section and on Twitter!